Slide selector switch assembly

ABSTRACT

A mechanical slide selector switch assembly is described which includes a plurality of slide switches having contacts designed to selectively engage a plurality of conductive strips printed on a board of insulating material. Each individual slide switch includes a ball bearing detent assembly which renders the slide switch more reliable and less susceptible to wear. The ball bearing detent assembly lifts the sliding switch contacts away from the printed conductive strips as the contacts are moved from one position to another, and thereby reduces contact wear and erosion of the printed conductive strips. Each slide switch also includes a digital position readout assembly including a flexible tape with numerals printed on it.

United States Patent 1 Granitz 1111 3,745,270 [4 1 July 10,1973

[ SLIDE SELECTOR SWITCH ASSEMBLY [75] Inventor: Richard Francis Granitz, Harrisburg,

[21] Appl. No.: 238,212

1,147,447 4/1969 Great Britain 200/16 D Primary Examinerl-lerman J. Hohauser Assistant Examiner-Gerald P. Tolin Att0rneyWilliam .l. Keating, Gerald K. Kita et al.

[57] ABSTRACT A mechanical slide selector switch assembly is described which includes a plurality of slide switches having contacts designed to selectively engage a plurality of conductive strips printed on a board of insulating material. Each individual slide switch includes a ball bearing detent assembly which renders the slide switch more reliable and less susceptible to wear. The ball bearing detent assembly lifts the sliding switch contacts away from the printed conductive strips as the contacts are moved from one position to another, and thereby reduces contact wear and erosion of the printed conductive strips. Each slide switch also includes a digital position readout assembly including a flexible tape with numerals printed on it.

.16 Claims, 4 Drawing Figures Patented July 10, 1973 2 Sheets-Sheet l Patented July 10, 1973 3,745,270

2 Sheets-Shoot 2 1 SLIDE SELECTOR SWITCH ASSEMBLY BACKGROUND OF THE INVENTION 1. Field Of The Invention This invention relates generally to mechanical switch assemblies, and more particularly to a mechanical switch assembly including a plurality of slide switches, and to the structure of the individual slide switches themselves.

2. Description Of The Prior Art Numerous slide switch assemblies are known in the prior art, such as those disclosed in U.S. Pat. No. 3,205,319 to Anderson et al. and U.S. Pat. No. 3,582,578 to Lockard. Both of these patents disclose devices in which a plurality of slide switches are employed in a matrix-like configuration to provide an electrical readout indicative of the positions or coordinates of a plurality of sliding contact switches. In general, switch assemblies of the type described in these patents include a printed circuit board on which a plurality of spaced, parallel conductive strips are imprinted. A plurality of slide switches are oriented perpendicular to the conductive strips on the printed circuit board, and include a first contact for slidably engaging the individual conductive strips on the printed circuit board. They also include a second contact which is generally in continuous engagement with a conductor or conductive strip associated with the slide switch itself, and which is oriented perpendicular to the conductive strips on the printed circuit board. A detent assembly is generally provided so that each of the slide switches can be positioned only at points where one of its contacts is in engagement with one of the conductive strips on the printed circuit board.

Unfortunately, slide switches of the type described above create substantial wear problems. For example, as the sliding contacts are wiped across the printed conductive strips time after time, small areas of the conductive strips are eroded, which can eventually cause an open circuit to occur. In addition, since the printed conductive strips are often positioned relatively close to one another, conductive material scraped from the various conductive strips by the sliding contacts may eventually bridge the gap between various pairs of conductive strips, thereby causing a short circuit to occur. Furthermore, the detent assembly may also deteriorate, due to the friction caused by poor quality bearing surfaces, causing the slide switch to stick, or otherwise become mechanically inoperative.

SUMMARY OF THE INVENTION Accordingly, one object of this invention is to provide a novel slide selector switch assembly.

Another object of this invention is to provide a novel selector slide switch assembly which is reliable and inexpensive to produce.

Yet another object of this invention is to provide a novel slide selector switch assembly which greatly reduces the amount of wear caused by contacts sliding over printed conductive strips.

A still further object of this invention is to provide a slide selector switch assembly including a highly durable and wear resistant detent assembly.

Another object of this invention is to provide a slide switch having a novel detent and contact assembly.

Yet another object of this invention is to provide a slide switch of especially durable and wear resistant characteristics.

A still further object of this invention is to provide a slide switch which is durable, provides a digital readout, is wear resistant, and yet is inexpensive to produce and relatively simple to assemble.

Briefly these and other objects of the invention are achieved by producing a slide selector switch assembly from a plurality of individual slide switches, each of which includes a ball bearing detent, a pair of resilient contacts, and a single, printed conductor, normally engaged by one of the contacts. Each slide switch is positioned perpendicular to a plurality of spaced conductive strips on a printed circuit board, which are selectively engaged by the other contact. The ball bearing detent assembly causes the contacts of the slide switch to be lifted away from both the printed conductor within the slide switch itself and from the conductive strips of the printed circuit board as the contacts are moved from one position to another. Thus, the contacts do not continuously slide across the various printed conductors, thereby reducing wear to both the contacts and the printed conductors.

BRIEF DESCRIPTION OF THE DRAWINGS A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a partially cut-away perspective view of a preferred embodiment of the slide selector switch assembly in the instant invention;

FIG. 2 is a partially cut-away side view of the slide switch structure of the present invention, showing the contacts in their normal operative position; 7

FIG. 3 is a partially cut-away side view of the apparatus illustrated in FIG. 2, illustrating the movement of the contacts as the switch assembly is moved between detent positions; and,

FIG. 4 is a cut-away end view taken along the lines 4 4 of the apparatus illustrated in FIG. 2.

DESCRIPTION OF THE FREFERRED EMBODIMENTS Referring now to the drawings, wherein like reference numerials designate identical of corresponding parts throughout the several views, and more particularly to FIG. I thereof, the slide selector switch assembly of the present invention is illustrated generally by the numeral 10. As is apparent from FIG. I, the slide selector switch assembly 10 includes a plurality of individual slide switches 12. Although only three individual slide switches 12 are represented in FIG. I, it will be apparent to those skilled in the art that any number of slide switches 12 may be included in the slide selector switch assembly 10. In addition, although only a single row of slide switches 12 is illustrated, it will also be apparent to those skilled in the art that multiple parallel rows of slide switches 12 may be included in the slide selector switch assembly 10, if desired. The purpose of the slide selector switch assembly 10 may be, for example, to provide both visual and electrical digital readouts indicative of manually selected numerical values. For example, the slide selector switch assembly 10 may be useful in various types of accounting and credit card purchase registering devices.

The slide selector switch assembly includes a top or cover panel 14, which may be constructed of a suitable material such as aluminium, steel sheet, or a suitable plastic. A plurality of apertures 16 are punched or drilled through the top panel 14 to permit inspection of visual readout attachments associated with each of the slide switches 12. A plurality of elongated apertures 18 are also provided in the top panel 14 to allow slide switch actuators 20 to be mounted above the top panel 14 in an easily accessible position. It will, of course, be apparent to those skilled in the art that one aperture 16 and one aperture 18 must be provided in the top panel 14 for each slide switch 12 included in the slide selector switch assembly 10.

A printed circuit board 22 is mounted below the individual slide switches 12, and forms the bottom panel of the slide selector switch assembly 10. On one surface of the printed circuit board 22 are located a plurality of printed conductive strips 24 thereby providing a plurality of conductor paths. The printed conductive strips preferably extend for the entire length of the slide selector switch assembly 10 and are relatively closely spaced and oriented parallel to one another. The printed conductive strips are intended to be selectively engaged by a contact 26, carried by each of the slide switches 12.

Referring now to FIGS. 2-4, the specific structure of each of the slide switches 12 is illustrated in more detail. Each slide switch 12 is constructed of a basic framework 28, which may be constructed either of metal or of a suitable plastic material. The invention does not require that the framework 28 be of conductive material, and therefore, where metal is used to construct the framework 28, only the structural properties of the metal need be considered, and its current conducting properties may be ignored. If metal is used, it may be coated partially or completely with an insulating layer of paint, or plastic material. The framework 28 is an elongated metal sheet formed with a generally C-shaped in cross-sectional configuration, defining a track as illustrated more clearly in FIG. 4. This C- shaped configuration of the framework 28 provides an upper channel portion 30 and a lower channel portion 32. A contact carrier block or carriage 34 slides in the upper channel portion 30 of the framework or track 28. As is shown more clearly in FIG. 4, a depending edge 36 of upper channel portion 30 is positioned in a groove in the upper portion of contact carrier block or carriage 34. Thus, the depending edge 36 of the upper channel portion 30 holds the contact carrier block or carriage 34 inside the channel portion of framework 28. The contact carrier block or carriage 34 includes an-open channel 38 in which a contact assembly 40 is movably mounted. The contact assembly 40 includes a contact body 42 of highly conductive metal, and a leaf spring 44, which is juxtaposed to the contact body 42 and biases the contact body 42 toward the lower channel portion 32 of framework 28. The contact body 42 and leaf spring 44 are friction fitted into a slot 46 in the rear portion of contact carrier block 34, and are thereby securely fixed to the contact carrier block. Previously mentioned contact 26 and a second contact 48 are formed integral with the contact body 42. However, the contacts 26 and 48 are separated from one another and are of the same length, although they are bent at different angles with respect to contact body 42. The ends of the contacts 26 and 48 are bent upperwardly to form foot portions 50 and 52, respectively. Each foot portion is then punched or deformed slightly to form a depending heel portion 54 and 56, respectively. The heel portions 54 and 56 are the only portions of the contact assembly 40 which actually engage the printed conductive strips used with the slide switch assembly. The heel portions 54 and 56 help to insure a positive contact between the contact assembly 40 and the conductive strips, such as 24, while minimizing wear to the conductive strips and to the contact assembly.

A narrow strip of printed circuit board material 58 is positioned within the lower channel portion 32 of framework 28. A layer of conductive material 60 is printed on the narrow strip 58 of printed circuit board material by conventional methods to provide a conductor path. The layer of conductive material 60 extends for substantially the entire active length of the slide switch 12, and is the conductor engaged by contact 48. As was described hereinabove, the layer of conductive material 60 is, like the slide switch 12 itself, oriented perpendicular to the plural printed conductive strips 24 on the printed circuit board 22.

The detent mechanism of the slide switch 12 includes a scalloped upper edge 62 of the lower channel portion 32 of framework 28. As is clearly shown in FIGS. 2 and 3, the scalloped edge 62 of the framework 28 includes a series of stable detent points or grooves 64 separated from one another by a plurality of unstable points, projections or peaks 66. A ball bearing 68, having substantially the same radius as the stable detent points or grooves 64, is provided to cooperate with the scalloped edge 62 of framework 28. The ball bearing 68 is movably positioned in a bore or aperture 70 which communicates between the bottom of contact carrier block 34 and the open channel portion 38 of the contact carrier block. A disk of insulating material 72, having substantially the same diameter as the bore 70 is coupled to the underside of the contact assembly 40 above the open bore 70. Thus, the leaf spring 44 resiliently biases the insulating disk 72 toward the interior of bore 70. Accordingly, when the slide switch 12 is assembled, the ball bearing 68 is positioned within the bore 70, and the insulating disk 72 is biased into engagement with the ball bearing 68 by the biasing force of leaf spring 44 and by the biasing force exerted by resilient contact body 42. Thus, the biasing force acting on ball bearing 68 tends to retain the ball bearing in one of the stable detent points or grooves 64, and simultaneously forces the contact carrier block or carriage upward, maintaining it in position in the upper channel portion 30 of framework 28. Thus, although contact carrier block or carriage 34 includes a lower or depending portion 74, which is positioned within the lower channel portion 32 of framework 28, the lower portion 74 does not engage or slide upon conductive layer 60. The lower portion 74 of contact carrier block or carriage 34 serves primarily as a guide member for the contact carrier block, and does not impose any wear on the conductive layer The ball bearing detent assembly, and the biasing assembly described above provide numerous advantages. For example, the use of a ball bearing greatly reduces the friction incurred in operating the slide switch and detent assembly. In addition, the ball bearing itself is of a very hard steel material, and is therefore highly resistant to mechanical wear or deformation. Accordingly, the use of a ball bearing improves the mechanical operation of the slide switch, and reduces the likelihood of mechanical failure due to wear or jammed parts. In addition, the biasing arrangement applies a strong biasing force to the detent assembly while it supplies only a much weaker biasing force to the contacts 26 and 48. This is due to the fact that the entire resilient biasing force of leaf spring 44 is applied to ball bearing 68, while the resilient biasing force of leaf spring 44 applied to the contacts 26 and 48 is modified by the fact that the contact body 42 and the contacts 26 and 48 extend far beyond the end of leaf spring 44. In fact, the biasing force which actually exists at the heel portions 54 and 56 of contacts 26 and 48 is little more than the biasing force which is exerted by the resiliency of the material of the contact body 42 acting alone. Thus, the biasing structure of the present invention provides a relatively firm detent biasing force, while providing only a relatively light contact biasing force. This feature improves the mechanical operation of the device, by providing a firm, positive detent motion, yet minimizes the wear to the printed conductors or conductor paths and contact structure of the device.

An end block 76 of insulating material is mounted at one end of the framework 28 to prevent the contact carrier block or carriage 34 from being moved beyond the end of the switch framework. The end block 76 is preferably mounted inside the upper and lower channel portions 30 and 32 of the framework 28. The end block 76 includes an arm portion 78 which extends along the interior of the upper channel portion 30 into the path of the contact carrier block or carriage 34. The arm 78 serves to engage the upper portion of the contact carrier block or carriage 34 to prevent further motion of the contact carrier block toward the end block 76. Thus, by suitably adjusting the length of the arm 78, the extent of travel of the contact carrier block or carriage 34 can be limited. However, the arm 78 must have a length which is at least sufficient to stop motion of the contact carrier block or carriage 34 before contact 48 engages end block 76, in order to prevent the contact 48 from being bent.

A terminal structure 80, which may be formed of any suitable conductive material, is positioned between the lower portion of end block 76 and the upper surface of the layer 60 of conductive material. The terminal structure 80 preferably includes upstanding ears 82 which engage opposite sides of the bottom portion of end block 76. A screw or other suitable fastening means 84 passes through openings in the lower channel portion 32 of framework 28, the narrow strip of printed circuit board material 58 which is positioned within the lower channel portion 32, the layer 60 of conductive material on the strip 58 and the terminal structure 80, and into an aperture in the end block 76. If a screw is used, the aperture in the end block 76 is internally threaded so that the screw may be threaded into the end block, securing the end block 76, the contact 80 and the narrow strip of printed circuit board material 58 in place. Clearly, other types of fasteners, such as rivets, may be used, as will be clear to those skilled in the art.

A tape carrier 86 is mounted to the end of framework 28 opposite that at which end block 76 is mounted. The tape carrier 86, which may be constructed entirely of a suitable plastic material, for example, includes a mounting block portion 88 which is of a suitable size to permit it to be inserted into the upper and lower channel portions 30 and 32 of the framework 28. A screw 90, or other suitable fastening means, is inserted through apertures formed in the framework 28 and in the narrow strip of printed circuit board material 58, and is threaded or otherwise fastened into the mounting block 88, fixing the mounting block in position. In addition to providing a means for holding the tape carrier 86 to the framework 28, the mounting block 88 also acts as a stop to prevent the contact carrier block 34 from being moved out of the framework 28. The tape carrier 86 also includes a cylindrical portion 92, having a cylindrical internal bore. A flexible tape 94, which may be formed of a suitable plastic material for example, is normally coiled within the cylindrical portion 92 of tape carrier 86. One end of the tape 94 is coupled to the slide switch actuator 20, for movement therewith. Thus, as the slide switch is actuated by movement of actuator 20, the tape 94 is withdrawn from the tape carrier 86. Suitable coded markings, such as conventional numerals or letters are preferably imprinted on the tape 94 at regular intervals, so that the tape provides a visual digital readout of the position of the switch contacts. The nature of both the tape 94 and the tape carrier 86 are such that the tape feeds itself into the carrier 86 when the switch actuator 20 is moved in one direction, and is extracted from the tape carrier 86 when the switch actuator 20 is moved in the opposite direction.

Attention is now directed to FIGS. 2 and 3, in which the unique operation of the detent mechanism described hereinabove is illustrated in more detail. In FIG. 2, the ball bearing 68 of the detent mechanism is shown resting in a stable position in one of the grooves 64. In this position, the heel 54 of the contact 26 is in engagement with one of conductive strips 24, and the heel 56 of contact 48 is in engagementwith the conductive layer 60. As the switch actuator 20 is moved, the contact carrier block or carriage 34 which is coupled to it is, of course, also moved. This causes the ball bearing 68 of the detent mechanism to rise out of the groove 64 in which it was positioned, and eventually reach an unstable point or peak 66 of the scalloped edge 32, as illustrated in FIG. 3. It will be understood, that the ball bearing 68 does not rest in the unstable position illustrated in FIG. 3, but moves quickly into another stable position 64. Thus, the rounded shape of the peaks 66 causes the ball bearing to essentially jump from one stable position 64 to the next. However, as the ball bearing 68 rises from a groove 64 toward a peak 66, it pushes against the lower surface of insulating disk 72, thereby counteracting the resilient biasing force of leaf spring 44, and raising or resiliently deflecting the contact body 42. This motion causes the heels 54 and 56 of the contacts 26 and 48 to be lifted out of engagement with the printed conductive strips 24 and 60, respectively. The heel portions 54 and 56 of the contacts 26 and 48 thus remain out of engagement with the printed conductive strips 24 and 60 as the slide switch is moved to its next position. At the next position, the ball bearing drops into a groove 64, and the heel 64 of the contact 26 then engages another-one of the printed conductive strips 24, while the heel 56 of the contact 48 simply engages another portion of the conductive strip or layer 50. The significant aspect of this motion resides in the fact that the contacts do not simply slide from one position to another, but are resiliently deflected and thereby lifted away from the printed conductive strips and are then allowed to resiliently deflect to positions lowered to reengage the printed conductive strips when the slide switch has reached another position. Accordingly, the contacts do not simply slide across the printed conductive layers, and therefore do not tend to abrade them, or wear them out. Thus, the detent motion of the present invention tends to prolong the life of the slide switch substantially, and tends to prevent electrical failures of the slide switch, caused, for example, by short circuiting between the printed conductive strips 24, or open cir cuiting caused by erosion of the printed conductive strips 24. In addition, wear along the layer 60 of the conductive material is reduced substantially by the motion of the detent assembly of the present invention.

Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. Accordingly,

What is claimed as new and desired to be secured by letters patent of the United States is:

1. In a slide switch assembly having a terminal strip, a plurality of spaced electrical conductor paths, track means extending generally transversely of said conductor paths, and a carriage carried by and displaceable along said track means, said carriage being provided with a contact means having a first resilient electrical contact and a second resilient electrical contact, with the first electrical contact electrically engageable on the terminal strip and with the second electrical contact electrically engageable successively in turn on each of the plurality of spaced electrical conductor paths upon displacement of said carriage along said track means, thereby to complete an electrical circuit between said terminal strip and any selected one of the plurality of spaced electrical conductor paths, the improvement comprising: a series of spaced projections provided along said track means, and detent means carried on said carriage, said detent means being displaceable along said track means and successively engageable on said projections upon displacement of said carriage along said track means, said detent means upon successive engagement with each of said projections being displaced against said contact means and thereby resiliently deflecting both said first and said second contacts respectively from said terminal strip and a corresponding one of said conductor paths to prevent excessive sliding displacement of said first and said second contacts slidably against said terminal strip and said corresponding one of said conductor paths, said detent means upon displacement of said carriage along said track means being successively in registration on positions each of which are located along said track means and adjacent to a respective one of said projections, said detent means upon successive registration with each said positions adjacent to said projections being displaced in a direction substantially away from said contact means to allow resilient deflection of said contact means together with said first and said second contacts into respective electrical engagement with said terminal strip and a corresponding one of said conductor paths, whereby said first and said second contacts are biased into and out of engagement with said terminal strip and a corresponding one of said conductor paths as said detent means is displaced along said track means.

2. The structure as recited in claim 1, wherein, said detent means is a spherical ball bearing received movably in an aperture provided in said carriage, said contact means is on said carriage adjacent one end of said aperture and resiliently biases said spherical ball bearing into continuous engagement with said track means, said ball bearing thereby being retained in said aperture and between said contact means and said track means.

3. The structure as recited in claim 1, wherein, said track means comprises an elongated metal sheet, with an edge of said metal sheet being provided with a generally scalloped configuration comprising said spaced projections over which said detent means is displaceable, said sheet being formed with a generally C-shaped cross sectional configuration to provide opposed channel portions receiving therebetween said carriage, said carriage being displaceable along said track means while between said opposed channel portions.

4. The structure as recited in claim 3, wherein, said detent means is a spherical ball bearing received movably in an aperture provided in said carriage, said contact means is on said carriage adjacent one end of said aperture and resiliently biases said spherical ball bearing into engagement with said track means, said ball bearing thereby being retained in said aperture and between said contact means and said track means.

5. The structure as recited in claim 4, wherein said detent means is a metal spherical ball bearing, and further including: an insert of electrical insulation material interposed between said contact means and said metal spherical ball bearing to prevent conduction of electricity from said contact means through said metal spherical ball bearing 6. The structure as recited in claim 1, wherein, at least one of either of said contact means, said detent means and said track means includes a surface thereof comprised of electrical insulation material preventing conduction of electricity from said contact means through said detent means and through said track means.

7. The structure as recited in claim 1, wherein said track means is fabricated from metal which is provided thereover with a surface of electrical insulation material.

8. The structure as recited in claim 1, wherein, said contact means has at least a portion provided thereover with a surface of electrical insulation material which is interposed between said contact means and said detent means to electrically insulate said contact means from said detent means.

9. The structure as recited in claim 8, wherein said track means is fabricated from metal provided thereover with a coating of a dielectric material.

10. A switch assembly for completing at least one electrical circuit between a first conductor and at least one conductor path selected from a plurality of conductor paths, comprising: a base, a plurality of spaced electrical conductor paths affixed to said base, a generally stationary supporting member mounted on said switch assembly in a fixed position relative to said base, a carriage mounted on said supporting member for displacement along said supporting member, a resilient and electrically conducting spring connected to said carriage for displacement therewith, said carriage having a portion provided with an aperture, detent means received in said aperture, said supporting member having a portion provided with a plurality of spaced projections thereon and a plurality of relatively recessed portions, each relatively recessed portion being adjacent one of said projections, said spring overlying said detent means and continuously resiliently biasing said detent means into continuous engagement with said supporting member portion which is provided with said projections thereon, said spring having an electrically conducting contact portion displaceable successively over said electrical conductor paths for electrical engagement successively in turn on each of said electrical conductor paths as said carriage is displaced along said supporting member, said detent means being displaceable together with said carriage along said supporting member for successive registration of said detent means with said projections and said relatively recessed portions of said supporting member, said detent means upon registration with each of said projections being deflected thereby against said spring to resiliently deflect said contact portion of said spring in a direction generally away from said base, said detent means upon registration with each of said relatively recessed portions of said supporting member being biased in a direction away from said spring to allow resilient deflection of said spring and said contact portion of said spring toward said base and into electrical engagement with a corresponding electrical conductor path, whereby as said contact portion of said spring is displaceable successively over said conductor paths said contact portion is allowed to deflect toward said conductor paths for successive electrical engagement in turn with each of said conductor paths, and with said contact portion being deflected away from said base to disengage said contact portion from a corresponding conductor path, and electrical terminal means electrically connected to said spring for making an electrical connection externally of said switch assembly, whereby said spring completes an electrical circuit between said terminal means and each of said conductor paths successively in turn as said carriage is displaced along said supporting member.

1 1. The structure as recited in claim 10, wherein, said supporting member includes an elongated track, with said carriage being slidably displaceable along said track.

12. The structure as recited in claim 11, wherein, said track is fabricated from an elongated metal sheet having the edges thereof formed to a generally C-shaped cross sectional configuration defining opposed channel portions, with said carriage being slidably retained substantially between said opposed channel portions, and one of said edges of said elongated metal sheet is provided with both said projections and said relatively re cessed portions over which said detent means is displaceable.

13. The structure as recited in claim 12, wherein, said detent means is a spherical ball bearing, and said spring is provided thereon with a quantity of electrical insulation material disposed between said spring and said ball bearing to prevent electrical conduction between said spring and said ball bearing.

14. The structure as recited in claim 12, wherein, said terminal means includes an elongated terminal strip, said spring includes a second contact portion displaceable over said terminal strip for electrical engagement therewith as said carriage is displaceable over said supporting member, said detent means upon engagement with each of said projections being biased by each of said projections against said spring to resiliently deflect said spring and said second contact portion of said spring in a direction generally away from said terminal strip, said detent means upon registration with each of said relatively recessed portions being biased thereby generally away from said spring and said second contact portion of said spring to allow resilient deflection of said second contact portion of said spring toward said terminal strip and into electrical engagement therewith, whereby as said second contact portion of said spring is displaceable over said terminal strip, said second contact portion alternatively is deflected away from said terminal strip and allowed to deflect toward said terminal strip for electrical engagement therewith.

15. A slide switch, comprising: a base having a plurality of spaced electrical conductor paths; an elongated track mounted on said base; said track being fabricated from an elongated metal sheet having opposed edges thereof formed to a generally C-shaped cross sectional configuration defining opposed channel portions extending along said elongated track; one of said opposed edges having thereon a series of projections and a relatively recessed portion adjacent a corresponding projection, one of said channel portions receiving an elongated electrical terminal in strip form; a carriage of dielectric material mounted between said opposed channel portions and being slidably displaceable along said track;

an electrically conducting and resiliently deflectable spring mounted on said carriage and having a first electrical contact for displacement over each of said electrical conductor paths in turn upon displacement of said carriage along said track; said electrically conducting spring also including a second electrically conducting contact for displacement over said electrical terminal in strip form; said carriage further including a ball bearing received in an aperture portion of said carriage; said ball bearing being located between said electrically conducting spring and said track; with said electrically conducting spring resiliently biasing said ball bearing continuously against said one of said op posed edges which is provided with said series of projections and relatively recessed portions; said ball bearing being displaceable over and successively engaging said series of projections and relatively recessed portions upon displacement of said carriage along said track; said ball bearing upon engaging each of said projections being biased against said spring to resiliently deflect said spring and said first and said second contacts generally away from said base and said terminal in strip form, thereby disengaging said first contact from electrical engagement with a corresponding electrical conductor path and disengaging said second contact from electrical engagement with said terminal of strip form; and said ball bearing upon engaging each of said relatively recessed portions being biased thereby generally away from said spring to allow resilient deflection of said spring and said first and said second contacts generally toward said base and said terminal in strip form, thereby allowing resilient deflection of said first contact into electrical engagement with a corresponding electrical conductor path and also allowing resilient deflecand said terminal in strip form in order to complete an electrical circuit path between said terminal in strip form and each of said electrical conductor paths in turn.

16. The structure as recited in claim 15, and further including: at least one fastener for securing together said base, said track and said terminal in strip form. 

1. In a slide switch assembly having a terminal strip, a plurality of spaced electrical conductor paths, track means extending generally transversely of said conductor paths, and a carriage carried by and displaceable along said track means, said carriage being provided with a contact means having a first resilient electrical contact and a second resilient electrical contact, with the first electrical contact electrically engageable on the terminal strip and with the second electrical contact electrically enGageable successively in turn on each of the plurality of spaced electrical conductor paths upon displacement of said carriage along said track means, thereby to complete an electrical circuit between said terminal strip and any selected one of the plurality of spaced electrical conductor paths, the improvement comprising: a series of spaced projections provided along said track means, and detent means carried on said carriage, said detent means being displaceable along said track means and successively engageable on said projections upon displacement of said carriage along said track means, said detent means upon successive engagement with each of said projections being displaced against said contact means and thereby resiliently deflecting both said first and said second contacts respectively from said terminal strip and a corresponding one of said conductor paths to prevent excessive sliding displacement of said first and said second contacts slidably against said terminal strip and said corresponding one of said conductor paths, said detent means upon displacement of said carriage along said track means being successively in registration on positions each of which are located along said track means and adjacent to a respective one of said projections, said detent means upon successive registration with each said positions adjacent to said projections being displaced in a direction substantially away from said contact means to allow resilient deflection of said contact means together with said first and said second contacts into respective electrical engagement with said terminal strip and a corresponding one of said conductor paths, whereby said first and said second contacts are biased into and out of engagement with said terminal strip and a corresponding one of said conductor paths as said detent means is displaced along said track means.
 2. The structure as recited in claim 1, wherein, said detent means is a spherical ball bearing received movably in an aperture provided in said carriage, said contact means is on said carriage adjacent one end of said aperture and resiliently biases said spherical ball bearing into continuous engagement with said track means, said ball bearing thereby being retained in said aperture and between said contact means and said track means.
 3. The structure as recited in claim 1, wherein, said track means comprises an elongated metal sheet, with an edge of said metal sheet being provided with a generally scalloped configuration comprising said spaced projections over which said detent means is displaceable, said sheet being formed with a generally C-shaped cross sectional configuration to provide opposed channel portions receiving therebetween said carriage, said carriage being displaceable along said track means while between said opposed channel portions.
 4. The structure as recited in claim 3, wherein, said detent means is a spherical ball bearing received movably in an aperture provided in said carriage, said contact means is on said carriage adjacent one end of said aperture and resiliently biases said spherical ball bearing into engagement with said track means, said ball bearing thereby being retained in said aperture and between said contact means and said track means.
 5. The structure as recited in claim 4, wherein said detent means is a metal spherical ball bearing, and further including: an insert of electrical insulation material interposed between said contact means and said metal spherical ball bearing to prevent conduction of electricity from said contact means through said metal spherical ball bearing.
 6. The structure as recited in claim 1, wherein, at least one of either of said contact means, said detent means and said track means includes a surface thereof comprised of electrical insulation material preventing conduction of electricity from said contact means through said detent means and through said track means.
 7. The structure as recited in claim 1, wherein said track means is fabricated from metaL which is provided thereover with a surface of electrical insulation material.
 8. The structure as recited in claim 1, wherein, said contact means has at least a portion provided thereover with a surface of electrical insulation material which is interposed between said contact means and said detent means to electrically insulate said contact means from said detent means.
 9. The structure as recited in claim 8, wherein said track means is fabricated from metal provided thereover with a coating of a dielectric material.
 10. A switch assembly for completing at least one electrical circuit between a first conductor and at least one conductor path selected from a plurality of conductor paths, comprising: a base, a plurality of spaced electrical conductor paths affixed to said base, a generally stationary supporting member mounted on said switch assembly in a fixed position relative to said base, a carriage mounted on said supporting member for displacement along said supporting member, a resilient and electrically conducting spring connected to said carriage for displacement therewith, said carriage having a portion provided with an aperture, detent means received in said aperture, said supporting member having a portion provided with a plurality of spaced projections thereon and a plurality of relatively recessed portions, each relatively recessed portion being adjacent one of said projections, said spring overlying said detent means and continuously resiliently biasing said detent means into continuous engagement with said supporting member portion which is provided with said projections thereon, said spring having an electrically conducting contact portion displaceable successively over said electrical conductor paths for electrical engagement successively in turn on each of said electrical conductor paths as said carriage is displaced along said supporting member, said detent means being displaceable together with said carriage along said supporting member for successive registration of said detent means with said projections and said relatively recessed portions of said supporting member, said detent means upon registration with each of said projections being deflected thereby against said spring to resiliently deflect said contact portion of said spring in a direction generally away from said base, said detent means upon registration with each of said relatively recessed portions of said supporting member being biased in a direction away from said spring to allow resilient deflection of said spring and said contact portion of said spring toward said base and into electrical engagement with a corresponding electrical conductor path, whereby as said contact portion of said spring is displaceable successively over said conductor paths said contact portion is allowed to deflect toward said conductor paths for successive electrical engagement in turn with each of said conductor paths, and with said contact portion being deflected away from said base to disengage said contact portion from a corresponding conductor path, and electrical terminal means electrically connected to said spring for making an electrical connection externally of said switch assembly, whereby said spring completes an electrical circuit between said terminal means and each of said conductor paths successively in turn as said carriage is displaced along said supporting member.
 11. The structure as recited in claim 10, wherein, said supporting member includes an elongated track, with said carriage being slidably displaceable along said track.
 12. The structure as recited in claim 11, wherein, said track is fabricated from an elongated metal sheet having the edges thereof formed to a generally C-shaped cross sectional configuration defining opposed channel portions, with said carriage being slidably retained substantially between said opposed channel portions, and one of said edges of said elongated metal sheet is provided with both said projections and said relatively recessed portions over which saiD detent means is displaceable.
 13. The structure as recited in claim 12, wherein, said detent means is a spherical ball bearing, and said spring is provided thereon with a quantity of electrical insulation material disposed between said spring and said ball bearing to prevent electrical conduction between said spring and said ball bearing.
 14. The structure as recited in claim 12, wherein, said terminal means includes an elongated terminal strip, said spring includes a second contact portion displaceable over said terminal strip for electrical engagement therewith as said carriage is displaceable over said supporting member, said detent means upon engagement with each of said projections being biased by each of said projections against said spring to resiliently deflect said spring and said second contact portion of said spring in a direction generally away from said terminal strip, said detent means upon registration with each of said relatively recessed portions being biased thereby generally away from said spring and said second contact portion of said spring to allow resilient deflection of said second contact portion of said spring toward said terminal strip and into electrical engagement therewith, whereby as said second contact portion of said spring is displaceable over said terminal strip, said second contact portion alternatively is deflected away from said terminal strip and allowed to deflect toward said terminal strip for electrical engagement therewith.
 15. A slide switch, comprising: a base having a plurality of spaced electrical conductor paths; an elongated track mounted on said base; said track being fabricated from an elongated metal sheet having opposed edges thereof formed to a generally C-shaped cross sectional configuration defining opposed channel portions extending along said elongated track; one of said opposed edges having thereon a series of projections and a relatively recessed portion adjacent a corresponding projection, one of said channel portions receiving an elongated electrical terminal in strip form; a carriage of dielectric material mounted between said opposed channel portions and being slidably displaceable along said track; an electrically conducting and resiliently deflectable spring mounted on said carriage and having a first electrical contact for displacement over each of said electrical conductor paths in turn upon displacement of said carriage along said track; said electrically conducting spring also including a second electrically conducting contact for displacement over said electrical terminal in strip form; said carriage further including a ball bearing received in an aperture portion of said carriage; said ball bearing being located between said electrically conducting spring and said track; with said electrically conducting spring resiliently biasing said ball bearing continuously against said one of said opposed edges which is provided with said series of projections and relatively recessed portions; said ball bearing being displaceable over and successively engaging said series of projections and relatively recessed portions upon displacement of said carriage along said track; said ball bearing upon engaging each of said projections being biased against said spring to resiliently deflect said spring and said first and said second contacts generally away from said base and said terminal in strip form, thereby disengaging said first contact from electrical engagement with a corresponding electrical conductor path and disengaging said second contact from electrical engagement with said terminal of strip form; and said ball bearing upon engaging each of said relatively recessed portions being biased thereby generally away from said spring to allow resilient deflection of said spring and said first and said second contacts generally toward said base and said terminal in strip form, thereby allowing resilient deflection of said first contact into electrical engagement with a corresponding electrical conductor pAth and also allowing resilient deflection of said second contact into electrical engagement with said terminal of strip form; whereby as said first and said second contacts are displaced over said plurality of conductor paths and said terminal of strip form, said first and said second contacts are successively deflected first out of electrical engagement and then into electrical engagement with corresponding electrical circuit paths and said terminal in strip form in order to complete an electrical circuit path between said terminal in strip form and each of said electrical conductor paths in turn.
 16. The structure as recited in claim 15, and further including: at least one fastener for securing together said base, said track and said terminal in strip form. 